The applicant has observed that beverage containers, especially aluminium alloy drink cans, have a deep countersink in their caps at a position adjacent to their rims.
As these containers are normally stored in an upright position, foreign materials such as dirt and other undesired matters find their way in the countersinks. Where the containers are kept with foods such as meat or fish in a refrigerator or cooler drips from such foods may fall in the countersinks. As the countersinks are relatively deep the foreign materials therein are not easily noticeable and are difficult to clean.
Further, for containers with beverage pouring apertures in their caps, beverage spillage tends to settle in the countersinks and on other parts of the caps.
Many people drink beverages directly from pour apertures in the caps. Bacteria, germs and diseases in the countersinks can come in contact with the drinkers. Accordingly these containers are not only unhygienic but also a health hazard.
The applicant has also noted that the caps of the beverage cans are normal secured to the can bodies by seaming with or without the assistance of an adhesive. For carbonated drinks the caps must have a minimum thickness in order that the seaming securement is sufficiently strong to prevent separation by internal pressures exerted by the carbonated drinks. This limitation is costly to can manufacturers as the use of thinner materials for the caps is currently not an option.